java

 1 package day07_addition; 2 import java.util.Arrays; 3 import java.util.Random; 4  5 //数组 伸缩、增删、位移、复制 6 public class ArrayFounderTrans { 7     public static void main(String[] args){ 8         int[] a = new int[6]; 9         Random rand = new Random();10         11         //初始化数组a[]12         for(int i=0;i<a.length;i++){13             a[i] = (int)(rand.nextInt(100));   /* a[i] = (int)(Math.random()*100); */14             System.out.print(a[i]+" ");15         }16         System.out.println();17         18         /*19          * 20         //数组缩进a[6]-->a[5]21         a = Arrays.copyOf(a, 5);22         for(int i=0;i<a.length;i++){23             System.out.print(a[i]+",");24         }25         */26         27         System.out.println("去掉第3个因素");28                         29         //方法1 复制：复制第4个元素及后面的元素，实现删除第3个元素30         int[] a1 = new int[5];31         int n = 3;32         System.arraycopy(a, 0, a1, 0, n-1);33         System.arraycopy(a, n, a1, n-1, a.length-n);34         for(int i=0;i<a1.length;i++){35             System.out.print(a1[i]+" ");36         }37         38         /*39          * 40         //方法2  数组按位交换，然后去掉最后元素，实现删除目标元素41         int temp;42         43 44         //从第3个元素开始移位45         for(int i=3;i<a.length-1;i++){
47             temp = a[i];
　　　　　　　　 a[i] = a[i+1];
               a[i+1] = temp;　　48         }49         */50     }51 }